Start pulling pub from its own repo.

sdk/lib/_internal/pub/test/validator/sdk_constraint_test.dart

Index: sdk/lib/_internal/pub/test/validator/sdk_constraint_test.dart
diff --git a/sdk/lib/_internal/pub/test/validator/sdk_constraint_test.dart b/sdk/lib/_internal/pub/test/validator/sdk_constraint_test.dart
deleted file mode 100644
index 4efb822037812bc33d33ca2634b05f00682a9310..0000000000000000000000000000000000000000
--- a/sdk/lib/_internal/pub/test/validator/sdk_constraint_test.dart
+++ /dev/null
@@ -1,48 +0,0 @@
-// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-import 'dart:async';
-import 'dart:convert';
-
-import 'package:http/http.dart' as http;
-import 'package:http/testing.dart';
-import 'package:path/path.dart' as path;
-import 'package:scheduled_test/scheduled_test.dart';
-
-import '../../lib/src/entrypoint.dart';
-import '../../lib/src/validator.dart';
-import '../../lib/src/validator/sdk_constraint.dart';
-import '../descriptor.dart' as d;
-import '../test_pub.dart';
-import 'utils.dart';
-
-Validator sdkConstraint(Entrypoint entrypoint) =>
-  new SdkConstraintValidator(entrypoint);
-
-main() {
-  initConfig();
-
-  group('should consider a package valid if it', () {
-    integration('has no SDK constraint', () {
-      d.validPackage.create();
-      expectNoValidationError(sdkConstraint);
-    });
-
-    integration('has an SDK constraint without ^', () {
-      d.dir(appPath, [
-        d.libPubspec("test_pkg", "1.0.0", sdk: ">=1.8.0 <2.0.0")
-      ]).create();
-      expectNoValidationError(sdkConstraint);
-    });
-  });
-
-  test("should consider a package invalid if it has an SDK constraint with "
-      "^", () {
-    d.dir(appPath, [
-      d.libPubspec("test_pkg", "1.0.0", sdk: "^1.8.0")
-    ]).create();
-    expect(schedulePackageValidation(sdkConstraint),
-        completion(pairOf(anyElement(contains('">=1.8.0 <2.0.0"')), isEmpty)));
-  });
-}